Vehicle air-conditioning system provided with seat air-conditioning unit

ABSTRACT

An air-conditioning system comprising a vehicle air-conditioner which uses a target blowing-out temperature as the basis to control an air outlet temperature in a cabin and a seat air-conditioning unit which sucks recirculated air into a seat and controls at least the seat air-conditioning air flow per unit time so as to perform seat air-conditioning, wherein the air-conditioning system increases the seat air-conditioning air flow when detecting that the vehicle speed is a predetermined value or less, calculates a correction amount for the target blowing-out temperature considered neutral in warmness sense level for the increased seat air-conditioning air flow, and uses the correction amount as the basis to correct the target blowing-out temperature.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a vehicle air-conditioning system in aconventional vehicle which controls a seat air-conditioning unit so asto reduce the amount of fuel consumption at the time the vehicle isstopped etc.

2. Description of the Related Art

Due to the rising need for conserving energy, the drop in fuel economydue to air-conditioner use at the time of idling has been surfacing asan issue. To counter the drop in fuel economy at the time of idling,raising the evaporator temperature etc. may be considered ascountermeasures, but simply raising the evaporator temperature of theair-conditioning system detracts from the passengers' feeling ofcomfort, so is not preferable. Note that, general air-conditioningsystems are described in detail in Japanese Unexamined PatentPublication No. 2006-76398, Automotive Air Conditioning, Tokyo DenkiUniversity Press, Kenichi Fujiwara et al., Sep. 20, 2009, pp. 88 to 94,etc.

As related art to deal with this issue, Japanese Unexamined PatentPublication No. 2000-142095 may be mentioned. In this art, hybrid carsor cars mounting economic running systems (cars with idling stopsystems) are adjusted in seat air-conditioning ability and compartmentair-conditioning ability so as to increase the engine stop time at timesother than ordinary operation and thereby save energy.

As opposed to this, in conventional vehicles, the engines have noautomatic stop, so art such as in Japanese Unexamined Patent PublicationNo. 2000-142095 cannot be used. In conventional vehicles, to maintainthe cooling ability of the vehicle air-conditioner while the engine isstopped (and while it is idling), it is necessary to operate thecompressor of the refrigeration cycle during that period. Usually theengine turning force is used to drive the rotation of the compressor, soto operate the compressor at the time of idling, it is necessary toraise the engine speed so that the engine does not stop (“idling upcontrol”). As a result, the problem arises that when theair-conditioning is on, compared with when the air-conditioning is off,the amount of fuel consumption ends up increasing.

SUMMARY OF INVENTION

The present invention was made in view of the above problem and has asits object to reduce the amount of fuel consumption at times inconventional vehicles other than when the vehicle is being driven (suchas at the time of idling).

To solve the above problem, the aspect of the invention of claim 1comprises an air-conditioning system comprising a vehicleair-conditioner which uses a target blowing-out temperature (target airoutlet temperature) as the basis to control an air outlet temperatureand with a seat air-conditioning unit which sucks recirculated air intoa seat and controls at least the seat air-conditioning air flow per unittime so as to perform seat air-conditioning, wherein theair-conditioning system increases the seat air-conditioning air flowwhen detecting that the vehicle speed is a predetermined value or less,calculates a correction amount for the target blowing-out temperatureconsidered neutral in warmness sense level for the increased seatair-conditioning air flow, and uses the correction amount as the basisto correct the target blowing-out temperature.

Due to this, in a conventional vehicle, there is less of a need for“idling up control” at the time of idling and it is possible to reducethe amount of fuel consumption at times other than normal driving (atthe time the vehicle is stopped or at the time of slow operation whenthe vehicle speed is a predetermined value A or less).

The aspect of the invention of claim 2 provides the aspect of theinvention of claim 1 characterized in that the vehicle air-conditionerof the air-conditioning system has at least an evaporator, air mix door,HVAC unit which has a heater core, and refrigeration cycle device whichoperates a compressor to supply the evaporator with low temperaturerefrigerant and in that the system calculates a target evaporator outlettemperature of the evaporator from the target blowing-out temperaturewhich has been corrected based on the correction amount so as to therebyreduce the compressor operating rate. Due to this, an advantageouseffect similar to the aspect of the invention of claim 1 further arises.

The aspect of the invention of claim 3 provides the aspect of theinvention of claim 1 characterized by calculating the correction amountby a map or calculation formula. Due to this, it is possible to quicklyand accurately calculate the correction amount. The effect of increaseof the air outlet temperature changes according to the vehicleenvironment, so it is possible to set effects of a plurality ofconditions in advance in the map and selectively use them in accordancewith input from sensors of the vehicle air-conditioner.

The aspect of the invention of claim 4 comprises the aspect of theinvention as set forth in claim 1, characterized by calculating acorrection amount based on an identical warmness sense level linecomprised of target blowing-out temperatures giving the same warmnesssense level for the increased seat air-conditioning air flow. Due tothis, it is possible to reduce the amount of fuel consumption andfurther improve the feeling of comfort of the passengers.

The aspect of the invention of claim 5 comprises the aspect of theinvention as set forth in claim 4 characterized by selecting anidentical warmness sense level line of a higher temperature to therebycalculate the correction amount so that the correction amount becomeslarger than the above identical warmness sense level line. Since fueleconomy is given priority to and a larger correction amount is set thanthe above identical warmness sense level line, it is possible to reducethe amount of fuel consumption more.

The aspect of the invention of claim 6 comprises the aspect of theinvention as set forth in claim 1 characterized in that the seatair-conditioning unit further comprises a switch for turning operationon and off and, when the switch is set at off and it is detected thatthe vehicle speed is a predetermined value or less, the system forciblyoperates the seat air-conditioning unit and uses the correction amountas the basis to correct the target blowing-out temperature. Due to this,even if the seat air-conditioning unit is off, it is possible to obtainan advantageous effect which is similar to the aspect of the inventionof claim 1.

The aspect of the invention of claim 7 comprises the aspect of theinvention of claim 6 characterized in that the switch is provided withswitch positions for setting the seat air-conditioning air flow instages and, when the switch position sets the seat air-conditioning airflow to a maximum air flow or less and the system detects the vehiclespeed is a predetermined value or less, the system forcibly makes theseat air-conditioning air flow the maximum air flow and uses thecorrection amount as the basis to correct the target blowing-outtemperature. Due to this, by simple control, it is possible to obtainadvantageous effects similar to the aspect of the invention of claim 1.

The aspect of the invention of claim 8 comprises the aspect of theinvention as set forth in claim 1 characterized by providing the seatair-conditioning unit with a heat exchanger.

The aspect of the invention of claim 9 comprises the aspect of theinvention as set forth in claim 1 characterized in that the seatair-conditioning unit blows air to a passenger who is seated at a seatby blowing out or sucking in air.

The present invention may be more fully understood from the descriptionof preferred embodiments of the invention, as set forth below, togetherwith the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view which shows an overall configuration of avehicle air-conditioner and a seat air-conditioning unit of one exampleto which the present invention is applied.

FIG. 2 is a block diagram which shows the system configuration of avehicle air-conditioner and a seat air-conditioning unit of one exampleto which the present invention is applied.

FIG. 3 is a general view of the effect of increase of the air outlettemperature which shows a relationship between an air flow of a seatair-conditioning unit and identical warmness sense level lines.

FIG. 4A and FIG. 4B are views which show the relationship between a seatair-conditioning air flow and a correction amount H.

FIG. 5A is a view summarizing air outlet temperature control, while FIG.5B is a view which shows a relationship between a target blowing-outtemperature (TAO) and a target evaporator outlet temperature.

FIG. 6 is a general flow chart which shows an embodiment of the presentinvention.

FIG. 7 is a general flow chart which shows another embodiment of thepresent invention.

FIG. 8 is a view showing seat air-conditioning of a Modification 4.

FIG. 9 is a view which shows a relationship between an air flow andidentical warmness sense level line of a seat air-conditioning unit ofthe Modification 4.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Below, referring to the drawings, embodiments of the present inventionwill be explained. In the embodiments, parts of the same constitutionswill be assigned the same reference signs and their explanations will beomitted. Parts of the same constitutions as the related art as well willbe assigned the same reference signs and their explanations omitted.

FIG. 1 is a schematic view which shows, as one example to which thepresent invention is applied, the overall configuration of a vehicleair-conditioner (including air-conditioning unit HVAC) and a seatair-conditioning unit 5. FIG. 2 is a block diagram which shows, as oneexample to which the present invention is applied, the systemconfiguration of a vehicle air-conditioner and a seat air-conditioningunit 5.

Each seat air-conditioning unit 5 is provided with a seat 3 comprised ofa back part 3 c and a seat part 3 b, a fan 51 which is arranged in aspace 6 which is formed at the bottom part of the seat 3, and a seatair-conditioning control device 37 b and seat air-conditioning controlpanel 54 which control the fan 51.

The back part 3 c is formed inside with a first duct 3 e whichcommunicates with the space 6. A plurality of air outlets 3 a are formedcommunicating with the first duct 3 e. The seat part 3 b is formedinside with a second duct 3 d which communicates with the space 6. Aplurality of air outlets 3 a are formed communicating with the secondduct 3 d.

The fan 51 guides recirculated air into the seat and blows it out towardthe air outlets 3 a. In the later explained Modification 4, a Peltierdevice or other electronic cooling device may be arranged in the space6. In this case, the seat air-conditioning control device 37 b controlsthe electronic cooling device. The seat air-conditioning unit to whichthe present invention is applied covers not the seat air-conditioningunit such as in Japanese Unexamined Patent Publication No. 2000-142095which is communicated with an HVAC for blowing air, but a seatair-conditioning unit of a type which guides recirculated air to theinside of the seat 3 and blows it out toward air outlets 3 a.

The seat air-conditioning control device 37 b is provided with a seatair-conditioning control program which is preset in a built in ROM. Itis electrically connected so as to enable not only operating informationfrom the seat air-conditioning control panel 54, but also controlinformation from the air-conditioning control means comprised of theair-conditioning control device 37 to be input and uses the operatinginformation and control information as the basis to control the fan 51.The seat air-conditioning control panel 54 is provided with a seatair-conditioning switch etc. which start and stop the seatair-conditioning operation and perform other operations and is arrangedat a position from which it can be operated by a passenger in a statesitting in the seat 3.

Next, the configuration of the air-conditioning unit 21 (HVAC) will beexplained.

At the upstream side of a fan duct 22, outside air intake ports 23 a, 23b which suck in air from outside the compartment (outside air) andrecirculated air intake ports 24 a, 24 b which suck in air inside thecompartment (recirculated air) are provided. The mixing ratio of therecirculated and outside air which are sucked in from the intake ports23 a, 23 b, 24 a, and 24 b is switched by the inside/outside air doors25 a and 25 b. The numbers of the intake ports of the outside air intakeports and recirculated air intake ports are not limited to the aboveillustrations and may be suitably set.

Inside the fan duct 22, a fan 26 is provided. At the downstream side ofthe fan 26, components forming part of the refrigeration cycle (notshown) such as an evaporator 28, air mix door 29, and heater core 30through which engine cooling water is circulated are provided. As iswell known, the opening degree of the air mix door 29 is adjusted toadjust the mixed ratio of the air which passes through the heater core30 and the air which does not pass through it and thereby adjust thetemperature of the conditioned air.

At the downstream side of the fan duct 22, a defrost opening 31 which isconnected through a duct to a defroster outlet which blows conditionedair out toward the front windshield of the vehicle, a face opening 32which is connected through a duct to face outlets which blow conditionedair out toward the upper bodies of passengers, and a foot opening 33which is connected through a duct to foot outlets which blow conditionedair out toward the feet of passengers are provided. At the upstreamsides of these openings 31, 32, and 33, control doors 34, 35, and 36 areprovided.

The air-conditioning unit 21 is arranged at the inside from theinstrumental panel at the front part of the compartment. The fan 51 andthe seat air-conditioning control device 37 b of each seatair-conditioning unit 5 are arranged inside of the seat 3 of thepassenger. The ,air-conditioning control device 37 a and the seatair-conditioning control device 37 b are configured to be electricallyconnected. The air-conditioning control device 37 a and the seatair-conditioning control device 37 b will be referred to together as the“air-conditioning control devices”.

The above configured air-conditioning unit 21 is controlled by theair-conditioning control device 37 a. This air-conditioning controldevice 37 a is provided with an air-conditioning control program whichis preset in a built in ROM. It receives detection signals Tr, Tam, Ts,and Hu of detection operations from sensors for detecting a heat load ofthe vehicle such as a recirculated air temperature sensor 38, outsideair temperature sensor 39, solar radiation sensor 40 for detecting theamount of solar radiation, and temperature sensor 41 and receivesoperating signals from the air-conditioning control panel 44 set insideof the instrument panel. Further, it runs the air-conditioning controlprogram to control the operating mode, outlet mode, air outlettemperature, fan flow, etc. of the conditioned air which is blown outfrom the air-conditioning unit 21 to the compartment.

The air-conditioning control panel 44, as one example, as is well known,is provided with an A/C switch which turns the air-conditioningoperation on and off, an auto switch which switches the operating modebetween automatic and manual, five outlet mode switches which manuallyswitch the outlets to “face”, “bi-level”, “foot”, “foot defroster”, and“defroster”, an intake mode switch which manually switches the intakemode to outside air intake/recirculated air circulation, a fan switchwhich manually switches the fan air flow, and a temperature settingswitch which manually sets the temperature setting becoming the targetvalue of the air-conditioning control.

The auto switch is an operating switch which enables automatic controlof switching of operating modes of the outlet mode switch, intake modeswitch, and fan switch. When the operating signals are input to theair-conditioning control device 37 a, the target blowing-out temperatureTAO which was calculated based on the temperature setting which thepassenger set and the recirculated air temperature Tr, outside airtemperature Tam, and amount of solar radiation Ts which were detected bythe recirculated air temperature sensor 38, outside air temperaturesensor 39, and solar radiation sensor 40 is used as the basis to findthe operating mode, air outlet temperature, fan air flow, and othercontrol amounts of the conditioned air which is blown out from theair-conditioning unit 21 to the inside of the compartment. These areoutput as control information to the air-conditioning unit 21 forair-conditioning by the air-conditioning unit 21.

The control of the automotive air-conditioning and the hardwareconfiguration of the system are not limited to the above example. Thecontrol which is described in the above-mentioned Automotive AirConditioning, pp. 88 to 94, p. 93, FIG. 5.20 may also be applied.

Below, the basic technical idea forming the foundation of the presentinvention will first be explained.

FIG. 3 is a general view of the effect of increase of the air outlettemperature which shows the relationship between the air flow of theseat air-conditioning unit and identical warmness sense level lines.This shows an example of the effect of raising the air outlettemperature by the seat air-conditioning. Here, the A/C(air-conditioning) air outlet temperature indicates the targetblowing-out temperature (TAO, see above Automotive Air Conditioning, pp.89 and 90). The target blowing-out temperature also means the target airoutlet temperature.

Referring to FIG. 3, the point that by operating the seatair-conditioning at the time of cooling, the effect is obtained of theair outlet temperature rising will be explained. The abscissa shows theair flow of the seat air-conditioning (recirculated air sucked in andblown out by predetermined air flow), while the ordinate shows the airoutlet temperature of the air-conditioner (target blowing-outtemperature TAO). The top bold line shows the upper limit of the“neutral” region of the identical warmness sense level lines. The bottombold line shows the lower limit of the “neutral” region of the identicalwarmness sense level lines. The “upper limit of the ‘neutral’ region”,as shown in FIG. 3, is the boundary line between “slightly warm” and“neutral”. The “lower limit of the ‘neutral’ region”, as shown in FIG.3, is the boundary line between “neutral” and “slightly cool”.

Here, if explaining as one example an identical warmness sense levelline of FIG. 3, at the time of a seat air-conditioning air flow of 0(m³/h), if the air outlet temperature is 17° C., the warmness senselevel falls in the “neutral” region. At this time, if making the seatair-conditioning air flow 20 (m³/h), even if the air outlet temperatureis about 22° C., the warmness sense level can be made the “neutral”region (see identical warmness sense level line of 17° C. of FIG. 3).That is, by operating the seat air-conditioning, even if causing the airoutlet temperature of the compartment air-conditioning to rise, it ispossible to obtain the identical warmness sense level of 17° C. The airoutlet temperature at the time of a seat air-conditioning air flow of 0(m³/h) was used to explain the identical warmness sense level line, butthe distance between the upper limit and lower limit of the “neutral”region is divided in level into three layers or other parallel regions.It is also possible to decide on identical warmness sense level linesrepresenting the same.

When the seat air-conditioning air flow is 20 (m³/h), as seen in FIG. 3,the neutral region is entered before about 25° C. For this reason, evenif making the air outlet temperature 25° C., the warmness sense levelcan still be made “neutral”. While the same level is aimed at in termsof warmness sense level, if fuel economy is given priority to, there isno need to stick to 17° C. identical warmness sense level. The airoutlet temperature can also be controlled while shifting to an identicalwarmness sense level line of another temperature within the “neutral”region above 17° C.

These results were first learned quantitatively as a result of R&D up tonow.

If briefly touching upon the method of finding these identical warmnesssense level lines, this is based on sensory analysis (evaluation byhuman subjects and thermal mannequins). That is, an identical warmnesssense level line is set by changing the seat air flow and air outlettemperature and reporting the warmness sense level. Note that sensoryanalysis has already been established as a known means.

The results of FIG. 3 can be explained quantitatively as follows: Theheat produced by the human body can be dissipated not only by thevehicle air-conditioner, but also from the seat part by seatair-conditioning (when seen from the human body), so even if reducingthe vehicle air-conditioner capacity by that amount, it is believed thatthe warmness sense level becomes equal.

Whether it is possible to use an identical warmness sense level linesuch as in FIG. 3 to control the air outlet temperature in thecompartment of a vehicle air-conditioner (HVAC unit) so as to reduce theamount of fuel consumption in a conventional vehicle other than at thetime of normal driving (that is, at the time of stopping etc.) will beexplained. In the winter, usually the cooling function is not used, sothe present invention is effective at the time of use of the coolingfunction in the summer.

Explaining this in more detail by a flow chart, the thinking in controlof the present embodiment is as follows: In the present embodiment, thevehicle air-conditioner is controlled based on the target blowing-outtemperature (TAO) so as to control the air outlet temperature in thecabin, while the seat air-conditioning unit sucks recirculated air intothe seat and controls at least the seat air-conditioning air flow perunit time for seat air-conditioning. At this time, when detecting thatthe vehicle speed is a predetermined value A or less, the systemincreases the seat air-conditioning air flow at that time (referred toas “reference seat air-conditioning air flow”), calculates a correctionamount H from the target blowing-out temperature (TAO) shown by thepoint where the seat air-conditioning air flow which has been increased(referred to as “increased seat air-conditioning air flow”) intersectsthe identical warmness sense level line, and uses this calculatedcorrection amount H as the basis to correct the target blowing-outtemperature (TAO). Of course, when detecting that the vehicle speed is apredetermined value A or less, it is also possible to increase the seatair-conditioning air flow Va and calculate the correction amount H ofthe target blowing-out temperature (TAO) considered neutral for theincreased seat air-conditioning air flow. In this case, any temperatureis possible so long as a target blowing-out temperature (TAO) which isincluded in the neutral region of FIG. 3.

An example of the case of the previously explained 17° C. identicalwarmness sense level line at the time of use of the cooling function inthe summer will be explained next. For simplification, it is assumedthat the seat air-conditioning is not operating and it is detected thatthe vehicle is in a stopped (or idling) state (or including a case wherethe vehicle speed is below a predetermined value A, for example, apredetermined value of 10 km/h or less, same below). The targetblowing-out temperature (TAO) of the vehicle air-conditioner at thistime is made 17° C. For the seat air-conditioning air flow of the seatair-conditioning unit, if detecting that the vehicle is stopped (or isidling), the seat air-conditioning air flow is automatically raised to20 (m³/h) (the value is not limited to 20 (m³/h) and is suitablydetermined). When making the seat air-conditioning air flow 20 (m³/h),the 17° C. identical warmness sense level line is crossed at about 22°C., so the target blowing-out temperature (TAO) of 17° C. is increasedby the correction amount 5° C. and the target blowing-out temperature(TAO) is controlled to 22° C. Due to this, thanks to the seat air flow,even if holding the target blowing-out temperature (TAO) high at 22° C.,a passenger can feed the same warmness sense level of 17° C.

In this way, in the case of cooling, instead of holding the targetblowing-out temperature (TAO) at 17° C., it is sufficient to hold astate of 22° C. which is 5° C. higher, so it is possible to lower thecooling ability. In conventional vehicles, there is no longer a need for“idling up control” at the time of idling and the amount of fuelconsumption at the time other than driving (that is, when the vehicle isat a stop) can be reduced.

That is, the target blowing-out temperature+correction amount isreplaced with the equivalent target blowing-out temperature (true targetblowing-out temperature), the HVAC is controlled from this true targetblowing-out temperature, and the compressor is controlled from thetarget evaporator outlet temperature. Originally, when not consideringthe seat air-conditioning air flow, the load on the compressor is large,but the target is set 5° C. higher, so the load becomes lighter andenergy is saved.

As explained above, in a conventional vehicle where the engine isconstantly operating, the issue is how to lower the fuel consumption. Itis possible to lower the compressor drive force and broaden the regionfor operation of the compressor (COMP) without “idling up control” wherethe fuel consumption rises. Note that,, if controlling the targetevaporator outlet temperature as one example to be proportional to thetarget blowing-out temperature, a more reliable effect is obtained inlowering the fuel consumption.

In the above case, for explanation of the present embodiment, it wasassumed that when detecting the vehicle was at a stop (or idling), theseat air-conditioning of the seat air-conditioning unit was notoperating. When it is operating, the control becomes as follows:

When detecting that the vehicle is at a stop (or is idling), the targetblowing-out temperature (TAO) is made 18° C. and the seatair-conditioning air flow (reference seat air-conditioning air flow) ismade 5 (m³/h). If finding the identical warmness sense level line fromFIG. 3, it is learned that in this case as well, it just happens to beon the 17° C. identical warmness sense level line. Usually, apredetermined identical warmness sense level line determined from thetarget blowing-out temperature (TAO) at the time the vehicle is stoppedand the seat air-conditioning air flow (reference seat air-conditioningair flow) is selected. Further, if detecting that the vehicle is stopped(or idling), it is assumed that the seat air-conditioning air flow isautomatically raised to 20 (m³/h). If making the seat air-conditioningair flow 20 (m³/h), the 17° C. identical warmness sense level line iscrossed at 22° C., so the target blowing-out temperature (TAO) of 18° C.is increased this time by the correction amount 4° C. and the targetblowing-out temperature (TAO) is controlled to 22° C.

The effect of increase of the air outlet temperature which is shown inFIG. 3 changes depending on the vehicle environment, so the effects of aplurality of conditions are set in advance, identical warmness senselevel lines corresponding to inputs from the sensors of theair-conditioning system are prepared, and the lines are selectivelyused. For this reason, by mapping in advance the effect of increase ofthe air outlet temperature explained in FIG. 3, it is possible to easilycalculate the raised temperature of the target blowing-out temperature(TAO) as the correction amount H in accordance with the current state ofthe seat air-conditioning (air flow is known from reference seatair-conditioning air flow and control voltage of fan).

That is, the present embodiment is an air-conditioning system where

-   -   the vehicle air-conditioner has an air-conditioning unit (HVAC)        and air-conditioning control devices (37 a, 37 b),    -   the air-conditioning control devices (37 a, 37 b) are provided        with at least a target blowing-out temperature calculating means        for calculating a target blowing-out temperature (TAO), a        correction amount calculating means for calculating a correction        amount (H), a seat air-conditioning air flow judging means for        detecting a seat air-conditioning air flow (Va) and setting an        increased seat air-conditioning air flow, a vehicle speed        judging means for judging if a vehicle speed is a predetermined        value (A) or less, and a means for calculating a target        evaporator outlet temperature from a target blowing-out        temperature (TAO) and correction amount (H), and    -   the seat air-conditioning air flow judging means and vehicle        speed judging means are used to calculate the correction amount        of the correction amount calculating means and the target        evaporator outlet temperature is calculated from the target        blowing-out temperature and the correction amount so as to        thereby enable a reduction of the compressor operating rate.

The above effect of increase of the air outlet temperature can be foundby a mathematical formula.

FIG. 4A and FIG. 4B are views showing the relationship between the seatair-conditioning air flow and the correction amount H.

As seen in FIG. 3, the identical warmness sense level lines of thedifferent temperatures are, by experience, substantially parallel as atrend. Therefore, the curves in the graph shown in FIG. 4A may also beapproximated by a mathematical formula. It is also possible to find andmap in detail the numerical values for each temperature. Furthermore, toraise the calculation speed, it is also possible to approximate theidentical warmness sense level lines for all temperatures as follows bya primary expression (line such as shown in FIG. 4B).

H=α·Va  (formula 1)

where,

H: correction amount (° C.)

α: constant (for example, 0.25)

Va: seat air-conditioning air flow (m³/h)

Next, the relationship between the target blowing-out temperature (TAO)and the target evaporator outlet temperature will be explained. FIG. 5Ais a summary of the air outlet temperature control, while FIG. 5B is aview which shows the relationship between the target blowing-outtemperature (TAO) and target evaporator outlet temperature. Note that,an outline of air outlet temperature control is given in the aboveAutomotive Air Conditioning, so has been omitted here.

Here, as is well known, the target blowing-out temperature (TAO) isfound as follows:

TAO=Kset−Tset−Kr·Tr−Kam·Tam−Ks·Ts+C

where,

Tset: temperature setting

Tr: compartment temperature

Tam: outside air temperature

Ts: solar radiation strength signal

Kset, Kr, Kam, Ks: gains of signals

C: constant

The temperature setting, outside air temperature, recirculated airtemperature, and solar radiation are explained in Automotive AirConditioning and other known vehicle air-conditioners, so explanationswill be omitted.

In the same way as Japanese Unexamined Patent Publication No.2006-76398, Automotive Air Conditioning, etc., in vehicleair-conditioner control (automotive air-conditioning), the heat load ofa vehicle is sensed and the above formula is used to calculate thetarget blowing-out temperature (TAO).

From this target blowing-out temperature, the outlet mode of the HVACand the air flow and air mix opening degree (A/M opening degree) aredetermined. The A/M opening degree is the mixing ratio of the heatexchanger (target evaporator outlet temperature T_(e), heater core(H/C)temperature T_(H)). The opening degree is determined from thetarget evaporator outlet temperatures T_(e) and T_(H) (engine watertemperature) to give the target blowing-out temperature (TAO).Therefore, in air-conditioning control of the HVAC unit, the targetblowing-out temperature (TAO) and the target evaporator outlettemperature are controlled in relation to each other.

The target evaporator outlet temperature is determined by the frost,defogging, comfortable humidity, and TAO (as an example, thecharacteristic shown in FIG. 5B results from the frost, comfortablehumidity, and TAO). The target blowing-out temperature (TAO) is used todetermine the target evaporator outlet temperature. The compressor iscontrolled from the target evaporator outlet temperature, so if thetarget blowing-out temperature (TAO) rises, the load on the compressorbecomes lighter and energy is saved.

Next, the seat air-conditioning switch will be explained. This switch(S/W) enables the air-conditioning ability of the seat air-conditioningto be changed by the passenger by his or her preference. At the veryleast, the switch is set to determine whether to operate the seatair-conditioning. This may be an OFF-ON two-stage switch or an OFF-Lo-Hior other multistage switch or may be a switch enabling a linear change.These environmental conditions are input to the ECU and are processedinside the ECU, then the HVAC, compressor, seat air-conditioning, orother actuator is driven.

When “Lo” is 10 (m³·h), “Mi” is 15 (m³·h), and “Hi” is 20 (m³·h), at thetime of “Lo”, by formula 1, the air outlet temperature can only beraised by H=0.25×10=2.5° C., but if changing this to 20 (m³·h), it canbe raised by up to 5° C., so it is possible to get the energy savingeffect exerted to the maximum extent. Therefore, the correction amountis calculated from the current state of the seat air-conditioningswitch, but if the current state of the switch position is not themaximum air flow, it is also possible to detect the idling state, thenautomatically make the seat air-conditioning maximum, then control thecorrection amount H to obtain the maximum effect. If explaining anexample of this, when detecting that the vehicle is at a stop (or isidling), if the current state of the switch position is the “Lo” 10(m³·h), it is possible to make it the “Hi” 20 (m³·h), determine theidentical warmness sense level line from the value of the targetblowing-out temperature (TAO) (or use formula 1) and control theair-conditioning to obtain the correction amount H. In this case,instead of the “Hi” 20 (m³·h), it is also possible to employ the maximumvalue of 20 (m³·h) or more.

When the seat air-conditioning switch is OFF, it is also possible tomake the correction amount H “0” and not correct the air-conditioning,but if detecting the idling state (or including the case where thevehicle speed is below a predetermined value A, for example, a 10 km/hor less predetermined value), it is also possible to forcibly operatethe seat air-conditioning. The predetermined value was made a 10 km/h orless predetermined value, but the invention is not limited to this. Thepredetermined value may also be suitably made 0 or 5 km/h or less. Forthe detection of the vehicle speed, there are many known arts in thearea of control for correction of vehicle air-conditioners, so themethod of detection will be omitted here.

FIGS. 6 and 7 are general flow charts which show embodiments of thepresent invention. Below, referring to FIG. 6, an outline of the flow ofcontrol of the system of one embodiment of the present invention will beexplained.

At step 1, the sensor outputs and set conditions are input to the ECU(same as related art).

At step 2, the input conditions are used as the basis to calculate thetarget blowing-out temperature (TAO) (same as related art).

At step 3, it is judged if the seat air-conditioning switch is on. Here,if the seat air-conditioning switch is selected as off, the routineproceeds to step 6. If selected as on (including “Lo”, “Hi”, etc.), theroutine proceeds to step 4.

At step 4, it is judged if the vehicle speed is under a predeterminedvalue A (for example, a 10 km/h or less predetermined value) (vehicle isat a stop (or idling) or other such state). If Yes, the routine proceedsto step 5, while if No, the routine proceeds to step 6.

At step 5, it can be judged that the seat air-conditioning is operatingand the vehicle is at a stop (or is idling), so this is a region where,without “idling up control”, the load for operating the refrigerationcycle of the vehicle would be difficult and therefore the correctionamount H is calculated.

Here, for example, when “Lo” is 10 (m³·h), “Mi” is 15 (m³·h), and “Hi”is 20 (m³·h), if “Lo” is selected, the seat air-conditioning air flow(reference seat air-conditioning air flow) is set to the “Lo” of 10(m³·h) when it is detected that the vehicle has stopped (or is idling)or is in another such state. Simultaneously, the seat air-conditioningair flow to be increased is set to a predetermined air flow setting, forexample, 20 (m³·h), the identical warmness sense level line such as inFIG. 3 is selected from the target blowing-out temperature (TAO)calculated at step 2 and the reference seat air-conditioning air flow,and the selected identical warmness sense level line is used to find thetarget blowing-out temperature (TAO) at the air flow setting andcalculate the correction amount H.

In this case, by mapping the effect of increase of the air outlettemperature which was explained in FIG. 3 in advance, it becomespossible to calculate the temperature able to be raised in accordancewith the current state of seat air-conditioning (reference seatair-conditioning air flow) as the correction amount H. Of course, it isalso possible to use formula 1 or another calculation formula forcalculation.

At step 6, it can be judged that the seat air-conditioning is notoperating, the air outlet temperature cannot be raised, or this is aregion where “idling up control” is not required, so the correctionamount H becomes 0.

At step 7, the system adds the target blowing-out temperature andcorrection amount and calculates the true target blowing-out temperaturefrom the map of the target blowing-out temperature and target evaporatoroutlet temperature shown in FIG. 5B (Step 8).

In this way, the HVAC is controlled from the target blowing-outtemperature, the compressor is controlled from the target evaporatoroutlet temperature, and the seat air-conditioning is controlled by apredetermined set air flow (or seat air-conditioning air flow to beincreased) (step 9, step 10, and step 11).

By repeating the content of control which was explained up to here, itbecomes possible to realize air-conditioning control and seatair-conditioning as in the past at the time the vehicle is being drivenand to keep the warmness sense level equal while reducing the compressordrive power (operating rate) when the vehicle is not being driven (or isidling).

FIG. 7 shows a modification of FIG. 6. Only the points changed will beexplained. The rest is similar to the earlier FIG. 6. In the case ofFIG. 6, when the seat air-conditioning switch was OFF, the correctionamount H was made 0 and the air-conditioning was not corrected, butafter detecting the idling state, the seat air-conditioning was forciblyoperated.

At step 3, if No, the routine does not immediately proceed to step 6, soat step 12, it is judged if the vehicle speed is under a predeterminedvalue A (for example, 10 km/h or less predetermined value), that is, ifthe vehicle is at a stop (or is idling) or another such state. If No,the routine proceeds to step 6, while if Yes, the routine proceeds tostep 13.

At step 13, the seat air-conditioning is forcibly turned on and apredetermined set air flow is used to control the seat air-conditioningair flow. In the same way as step 5, the correction amount H iscalculated. The remainder is similar to the case of FIG. 6.

As other embodiments of the present invention, the followingmodifications may be considered.

Modification 1

In the embodiments which were explained up to here, the explanation wasgiven based on the identical warmness sense level, but to give priorityto the fuel economy, it is also possible to make the correction amountlarger than the identical warmness sense level line which was explainedin FIG. 3. As the method of for increasing the correction amount, it ispossible to shift to an identical warmness sense level line of apredetermined higher temperature (within neutral region) to calculatethe correction amount.

Modification 2

In the embodiments explained up to here, the correction amount iscalculated from the current state of the seat air-conditioning switch,but when the current state of the switch position is not the maximum airflow, after detecting the idling state, it is also possible toautomatically make the seat air-conditioning the maximum air flow (“Hi”or the higher “Max” value), then set the correction amount H to give themaximum effect in air-conditioning control. When the switch is used toset “Lo” or “Mi” other than the maximum (“Hi”), for example, when “Lo”is 10 (m³·h), “Mi” is 15 (m³·h), and “Hi” is 20 (m³·h), at the time of“Lo”, it is only possible to raise the air outlet temperature byH=0.25×10=2.5° C., but if changing this to 20 (m³·h), the temperature israised up to 5° C., so the energy saving effect can be exerted to themaximum.

Modification 3

The effect of increase of the air outlet temperature which is shown inFIG. 3 changes depending on the vehicle environment, so it is alsopossible to set in advance advantageous effects of a plurality ofconditions and selectively use the conditions in accordance with inputsfrom sensors of the air-conditioning system.

Modification 4

The effect of increase of the air outlet temperature which is shown inFIG. 3 was explained with reference to a fan seat in which only air isonly blown for seat air-conditioning, but seat air-conditioning alsoincludes types where a heat exchanger (cooler) 52 (Peltier device etc.)is mounted, so it is also possible to set in advance a plurality ofconditions including not only the air flow, but also the heat exchangercapacity and selectively use them in accordance with the air flow andheat exchanger capacity or air outlet temperature. FIG. 8 is a viewwhich shows seat air-conditioning of Modification 4. FIG. 9 is a viewwhich shows a relationship between an air flow of a seatair-conditioning unit and identical warmness sense level lines ofModification 4. In this case, the effect of increase of the air outlettemperature rises in accordance with an increase of the seatair-conditioning air flow (see broken line to solid line).

Modification 5

The air circulation method of seat air-conditioning was explainedassuming a blowing out type, but a suction type is completely the same.In this case, the effect of increase of the air outlet temperature ofFIG. 3 differs, so this has to be found by experiments.

While the invention has been described by reference to specificembodiments chosen for purposes of illustration, it should be apparentthat numerous modifications could be made thereto by those skilled inthe art without departing from the basic concept and scope of theinvention.

1. An air-conditioning system comprising a vehicle air-conditioner whichuses a target blowing-out temperature as the basis to control an airoutlet temperature and a seat air-conditioning unit which sucksrecirculated air into a seat and controls at least the seatair-conditioning air flow per unit time so as to perform seatair-conditioning, wherein the air-conditioning system increases saidseat air-conditioning air flow when detecting that the vehicle speed isa predetermined value or less, calculates a correction amount for thetarget blowing-out temperature considered neutral in warmness senselevel for the increased seat air-conditioning air flow, and uses saidcorrection amount as the basis to correct said target blowing-outtemperature.
 2. An air-conditioning system as set forth in claim 1,characterized in that said vehicle air-conditioner of saidair-conditioning system has at least an evaporator, air mix door, HVACunit which has a heater core, and refrigeration cycle device whichoperates a compressor to supply the evaporator with refrigerant and inthat the system calculates a target evaporator outlet temperature ofsaid evaporator from said target blowing-out temperature which has beencorrected based on said correction amount so as to thereby reduce saidcompressor operating rate.
 3. An air-conditioning system as set forth inclaim 1, characterized by calculating said correction amount by a map orcalculation formula.
 4. An air-conditioning system as set forth in claim1, characterized by calculating a correction amount based on anidentical warmness sense level line comprised of target blowing-outtemperatures giving the same warmness sense level for said increasedseat air-conditioning air flow.
 5. An air-conditioning system as setforth in claim 4, characterized by selecting an identical warmness senselevel line of a higher temperature to thereby calculate the correctionamount so that the correction amount becomes larger than the aboveidentical warmness sense level line.
 6. An air-conditioning system asset forth in claim 1, characterized in that said seat air-conditioningunit further comprises a switch for turning operation on and off and,when said switch is set at off and it is detected that the vehicle speedis a predetermined value or less, the system forcibly operates said seatair-conditioning unit and uses said correction amount as the basis tocorrect said target blowing-out temperature.
 7. An air-conditioningsystem as set forth in claim 6, characterized in that said switch isprovided with switch positions for setting said seat air-conditioningair flow in stages and, when said switch position sets said seatair-conditioning air flow to a maximum air flow or less and the systemdetects the vehicle speed is a predetermined value or less, the systemforcibly makes said seat air-conditioning air flow the maximum air flowand uses said correction amount as the basis to correct said targetblowing-out temperature.
 8. An air-conditioning system as set forth inclaim 1, characterized by providing said seat air-conditioning unit witha heat exchanger.
 9. An air-conditioning system as set forth in claim 1,characterized in that said seat air-conditioning unit blows air to apassenger who is seated at a seat by blowing out or sucking in air.